LIFE HIstoKY OF CATTLE TICK. 18 
lays numerous eggs, which are usually nunc or less clustered together. The^arva 
upon hatching possesses three pairs <>f legs, the fourth pair being added during the 
first molt. Either the hexapod or the octopod form maj attack its host. 
From the foregoing it will be seen thai the cattle tick, Like other 
ticks, passes through the following stages: Egg, larva (six-legged 
form) . nymph, and adult . 
The eggs are nearly round, dark brown in color, and deposited in 
large masses, held together by the gummy secretion with which the 
female coats each egg as it is deposited. r I ne next stage*, known as 
the >oi^\ tick, differs remarkably from the later stages in the fact thai 
si\ instead of eight legs are present. r I ne stigmata are located be- 
tween the second and third coxa\ just anterior to the third coxa 1 , 
and problematic indications are seen between the 6rs1 and second 
coxa 1 . Xo distinct genital or anal opening can be seen in this stage. 
The anterior legs are much larger than the others. They are waved 
violently through the air when the seed ticks are disturbed either by the 
approach of a host or in any other way. After some time the seed 
tick molts and the next, or nymphal stage, is provided with eight 
legs. The absence of the genital opening will differentiate this stage 
from the following one. Ticks in the njmphal stage are frequently 
referred to in the South as " yearling ticks." After a second molt 
the adult form is reached. Copulation then takes place, and after 
engorgement the female drops to the ground for the purpose of depos- 
iting eggs. 
THE LIFE HISTORY OF THE CATTLE TICK. 
As pointed out by Morgan the most important fact about the cattle 
tick ( Margaropus annulatus Say), from the standpoint of practical 
control, is that the time of development on the animal is always shorter 
than the total of the preoviposition, oviposition, and incubation 
periods. This gives the farmer an opportunity .to free his cattle and 
pastures of ticks by the same process of rotation. As a foundation 
for the surest and most economical procedure an accurate knowledge 
of the variations of the periods in the life history of the tick under 
different conditions is absolutely essential. Our effort in this bulletin 
is in a measure to supply this information. The work has been prin- 
cipally to obtain data necessary in the pasture eradication and feed- 
lot systems of eradication. We have consequently studied the devel- 
opment of the tick both dining its existence on the animal, by means 
of a steer procured for that purpose, and during its life, under various 
conditions, when not attached to the host. 
